Pneumatic Air Preparation - FRL Units

Air Preparation in Pneumatic Systems:
FRL Units

The life of a pneumatic system depends directly on the quality of the compressed air used. Comprehensive guide on FRL units.

December 20, 2025

8 min read

BRS PROSES Engineering Team

The life of a pneumatic system depends directly on the quality of the compressed air used. Air preparation units consisting of Filter, Regulator and Lubricator (FRL) are the first line of defense protecting system components against corrosion, wear, and clogging.

Why Air Preparation?

Air coming from the compressor is hot, humid, and dirty. If this air goes directly to valves or cylinders, it damages seals and causes rusting. The FRL unit cleans the air (F), regulates pressure (R), and lubricates if necessary (L).

FRL Unit Components

1. Filter

Condenses water vapor in the air and traps solid particles. 40 micron filters are generally used for standard pneumatic valves, and 5 micron filters for precision equipment.

Centrifugal Effect: Separates water from the air.
Automatic Drain: Allows accumulated water to be discharged without manual intervention.

2. Regulator

Keeps system pressure constant. Even if the compressor pushes 8-10 bar, the machine usually needs 6 bar. The regulator prevents unnecessary air consumption and fluctuations.

Critical Warning: Lubricator

Most modern pneumatic cylinders and valves contain factory-applied "lifetime lubrication" grease. Adding external lubricant (conditioner oil) to these systems can wash away the internal grease and cause failure. Do not use a lubricator unless specified by the manufacturer.

ISO 8573-1 Air Quality Standards

International standard determining how clean the air should be according to your application.

Class	Particle Size (µm)	Water Pressure Dew Point (°C)	Oil Quantity (mg/m³)
Class 1	0.1 - 0.5	-70°C	0.01
Class 2	0.5 - 1.0	-40°C	0.1
Class 3	1.0 - 5.0	-20°C	1.0
Class 4	> 5.0	+3°C	5.0

BRS PROSES FRL Solutions

We select the right air preparation units for your industrial facilities, perform their assembly, and carry out periodic maintenance.

Our Services:

Air consumption analysis
Correct filter/regulator selection
Leak detection and elimination
Automation panel assembly

Air Preparation in Pneumatic Systems: FRL Units